Heat exchange towers are in wide use in industry. These heat exchange towers include, for example, a variety of well known cooling towers, which in some instances may be used to cool process water from an industrial operation. Such cooling towers often involve the spraying of a relatively warm water over a fill pack. The fill pack often includes parallel adjacent corrugated sheets so that the water will tend to have a significant surface area contact with the ambient air, and thus be cooled by the ambient air. Fill packs also may be utilized simply to have air passing through them for heat exchange between one air path and another air path.
In some instances, the fill packs are made up of a plurality of corrugated sheets, with the sheets running generally in parallel to each other and being laid in parallel with each other. The corrugated sheets generally have their corrugations either offset from each other or at an angle to each other so that air spaces are formed in between the sheets. The sheets may also have, in addition to, or instead of corrugations, other registration features or aligned dimples or other indentations which can be aligned with each other in order to provide registration and/or a desired spacing between the sheets.
A simple stack of corrugated sheets lying on top of each other or adjacent each other can have the disadvantage that such an assembled pack is not very rigid, and thus can be susceptible to damage. Further, if the sheets are merely adjacent each other there may be a tendency for some spacing to occur between the sheets. In addition, sheets which are not somehow mechanically attached to each other can suffer the disadvantage of a sheet falling out, especially since in many instances the sheets are oriented vertically in their final installation.
Further, a large cooling tower installation may require a very large volume of fill pack material. It has been known to create medium size modules each having a large number of sheets, and to be able to transport and handle these modules individually at the fabrication site of a tower. It is desirable in some environments that these modules have all the sheets well attached together in order to facilitate such handling and installation.
Many methods have been known for creating a fill pack module. In this application, the concepts of a multi-sheet fill pack, and a multi-sheet fill pack module, will be used interchangeably after fill packs are assembled with the sheets horizontally stacked, but one then installed with the sheets vertically oriented. One method has involved the supply of a first single sheet and a second single sheet, with first and second sheets being bonded together using heat bonding or using an adhesive or solvent material. Then, a third single sheet is laid onto the first two sheets, again with an adhesive or bonded material in between. A fourth single sheet is laid on to the three sheets using an adhesive or bonded material, and so on. This method has proved effective, but can be labor and time intensive. Another method for creating a fill pack has been to assemble all the sheets, without any bonding, and to hold them together using a fixture, and then to apply some form of solvent, either before stacking the sheets, or by running or deluging the solvent through the spaces in between the sheets. Then, the entire fill pack is cured or allowed to bond and the pack can be removed. This method is also successful, but has the disadvantage of requiring a relatively elaborate fixture and also the need to use solvents, which may present environmental or safety issues such as VOC emissions or combustion hazards. Large quantities of solvent used to deluge the pack contact points exacerbate environment and safety issues. The deluge method may have the further disadvantage of not reliably bond contact points throughout large packs.
It would be desirable to have a structure and method for fill pack construction, which could be cost effective, easy, convenient, and/or reduce the use of chemicals compared to some prior art methods.